Tux is the mascot of Linux, and as such a well-known character, which has already a few games, which unfortunately appear to be less known by non-linux people. For example a racing game, called Super Tux Kart. The graphics of the early versions of this game are somewhere between Mario Kart 64 and Diddy Kong Racing, I think. Meanwhile, with newer versions the graphics get better.
Anyway, it is a funny game, and it is free software, released under the GPL.
The music in the newer versions differ from the ones in the old versions, and unfortunately, they dropped my favourite melody from the 0.4 version, namely the melody from the Star Track. Its no amazing melody, but it can compete with other music from commercial games.
The original ogg-file can be found under https://supertuxkart.svn.sourceforge.net/svnroot/supertuxkart/main/tags/0.4/oggs/tk5a.ogg (at least until SourceForge changes its svn-viewer-architecture), according to https://supertuxkart.svn.sourceforge.net/svnroot/supertuxkart/main/tags/0.4/data/licenses it is released under GPLv2 or later – which is confusing, because there is no source code (which one would have to make accessible when reusing this file). Anyway. For anybody not capable (or willing) to play Ogg Files, there is also a youtube-video, enjoy: